# Optimization-Based Bound Tightening using a Strengthened QC-Relaxation of the Optimal Power Flow Problem

@article{Sundar2018OptimizationBasedBT, title={Optimization-Based Bound Tightening using a Strengthened QC-Relaxation of the Optimal Power Flow Problem}, author={Kaarthik Sundar and Harsha Nagarajan and Sidhant Misra and Mowen Lu and Carleton Coffrin and Russell Bent}, journal={ArXiv}, year={2018}, volume={abs/1809.04565} }

This article develops a strengthened convex quadratic convex (QC) relaxation of the AC Optimal Power Flow (AC-OPF) problem and presents an optimization-based bound-tightening (OBBT) algorithm to compute tight, feasible bounds on the voltage magnitude variables for each bus and the phase angle difference variables for each branch in the network. Theoretical properties of the strengthened QC relaxation that show its dominance over the other variants of the QC relaxation studied in the literature…

## 15 Citations

Tightening QC Relaxations of AC Optimal Power Flow Problems via Complex Per Unit Normalization

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It is shown that in meshed networks with parallel lines, BIM dominates BFM, and novel constraints to make them equivalent in general are proposed, tightening the second-order cone relaxation gap on test cases in the ‘PG Lib’ optimal power flow benchmark library.

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An Ecological Robustness Oriented Optimal Power Flow for Power Systems' Survivability

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—Traditional optimal power ﬂow (OPF) ensures power systems are operated safely at minimum cost. Recent disasters have highlighted that a focus on minimizing cost can result in a fragile system, such…

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